1. Technical Field
The embodiments described and claimed herein relate generally to wheelchair securement methods, systems, and devices for wheelchair accessible vehicles.
2. Background Art
Proper use of a wheelchair securement system (also referred to as a wheelchair tie-down system) is important for the safe transportation of people traveling on wheelchairs. In small spaces, such as the space in a rear-entry vehicle, it is important that the wheelchair securement system is simple and safe to use. Occupants in wheelchairs who are not able to transfer or move into a vehicle chair usually depend on the wheelchair securement assemblies (also referred to as wheelchair tie-downs or wheelchair tie-down assemblies) to safely secure their wheelchair while traveling. Proper securement of a wheelchair is critical so that an occupant restraint system can also be safely applied to the occupant. This represents a challenge especially in a public transportation environment as there are many different types of wheelchairs and therefore the tie-down assemblies need to be universally applicable in order to safely secure the majority of them. On a private vehicle however, the wheelchair tie-down can be tailored to a specific wheelchair and occupant which may assist in reducing the challenges of proper securement of the wheelchair and the occupant.
Existing securement systems used in smaller, more compact vehicles or tight or confined wheelchair spaces suffer from many drawbacks, some of which are described below. Such spaces, like existing rear-entry vehicles (also referred to as rear-entry wheelchair accessible vehicles), do not offer enough space for the front of a wheelchair to be secured after it is in place in the securement area of the vehicle. As such, it is important for a fully integrated system in a rear-entry vehicle to be useable from behind the wheelchair passenger. Similarly, in other confined wheelchair securement areas, it is difficult to reach a portion of the wheelchair needed securement once it is in place. In these vehicles, it may be important for a fully integrated system to be usable from in front of the wheelchair passenger.
In addition, there is a trend towards using smaller vehicles with confined wheelchair securement areas, such as smaller rear-entry vehicles in many global markets for varying reasons such as size, weight, and/or fuel efficiency. Smaller rear-entry vehicles generally tend to have a small installation or securement footprint for wheelchairs. Current 4-Point Retractor Systems can be very difficult to use since the space requirement is larger than the space available in a rear entry vehicle. Typically the retractors require some type of track and/or anchor points on the floor; two on the front and two on the rear. The retractors have a limited amount of webbing and require that the wheelchair be in place inside the vehicle before securing the front tie downs which is very challenging since the wheelchair occupies nearly all space available. The rear retractors need to be removable so the wheelchair can be pushed into position. This means that the refractor assemblies have to be stored someplace else inside the vehicle, which means additional steps and time to secure the wheelchair. Additionally the rear retractors are not permanently attached and can be lost or forgotten outside the vehicle. As such, any design for a wheelchair securement system in rear-entry vehicle that takes less space in the vehicle, can potentially have a large impact on the size of wheelchairs that can be secured.
Third, the securement assemblies, and specifically the restraints, may not secure the wheelchair at optimal angles. Smaller installation spaces and larger wheelchairs make this increasingly difficult since the optimal restraint angle is a function of the space size, size of wheelchair and restraints and location of restraints. It is critical to reduce the footprint of the securement mechanism or system, therefore creating more space for optimal angles, especially in the rear of the wheelchair after the wheelchair is secured in the vehicle.
Accordingly, there is a need for an improved securement system for securing wheelchairs in vehicles.